The background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
Computer systems, such as personal computers, servers, or clusters of computers, utilize non-volatile storage to store and retrieve data. Storing data in non-volatile storages allows the associated computer systems to access the data after power cycling and allows other computer systems to access the same data via a network.
Due to on-going demands for data storage units that can perform high speed storing and retrieval, data storage units on both consumer and enterprise levels have incorporated one or more internal volatile memory blocks to act as an intermediate storage for buffering before committing the data into the non-volatile memory units during storage cycle or for caching upon requests to retrieve data from non-volatile memory units into the host system during fetch cycles.
In order for a computer system to provide a robust, solid, secure, and deterministic operation, the non-volatile storage unit must guarantee the security and storage of internal volatile memory content during unpredicted, unscheduled power loss. If the non-volatile storage unit does not have a power back-up circuitry while the system experience unpredicted, unscheduled power loss, the content stored in the volatile memory within non-volatile storage unit will be lost and unrecoverable.
One solution is for non-volatile storage units to encompass a back-up power unit, such as a back-up battery or a back-up capacitor, for providing the required power to transfer the entire content stored in the volatile memory block within the non-volatile storage unit to the non-volatile storage elements.
Due to constant increasing demand of both consumer and enterprise non-volatile storage unit capacity today, the average non-volatile storage units has a capacity in the range of 4 to 8 terabytes (4,000,000,000,000-8,000,000,000,000 bytes). The internal volatile memory block size to effectively buffer or cache the required content capacity has a direct correlation to non-volatile storage units capacity. As the capacity of non-volatile storage units increases, the capacity of internal Volatile memory block will proportionally increase.
In order for the content stored in the volatile memory block to be safely and persistently saved in the non-volatile memory unit, the controller of the non-volatile memory unit need to complete the current ongoing operation, and then send the entire content stored in the volatile memory block through one or more internal blocks, such as a security block, a compression and Decompression block, an error correction circuitry (ECC) block, a scrambler and de-scrambler block, prior to storing the final processed content into the non-volatile memory array.
The larger the volatile memory block size, the higher power consumption is required to safely and permanently store the content stored in the volatile memory block in the non-volatile storage unit. The increase of power consumption translate to a larger battery or capacitor block to be incorporated into the non-volatile battery unit, which in turn requires large enough additional real state on the non-volatile storage unit, additional power requirements for charging and maintenance of the power holding blocks, additional thermal (i.e., heat dissipation) requirement for the large battery or super capacitor, and additional cost.
Thus, there remains a need for a system and method that improves the power consumption for non-volatile memory units to recover data during a power failure event.